Burglar-alarm.



0. DUNKEL.

`BURGMR ALARM. APPLI@MISION4 FILED NOV. 21. 1905.

l f /f Y@ m l mams PATENTED AUG. 28, 1906.

OTTO DUNKEL, OF LINCOLN, NEBRASKA.

BUnGLAR-ALARM.

lv o. 829,5 l 5.

Specification of Letters Patent.

Patented Aug. 28, 1906.

Application iild November 21, 1905. Serial No. 288.506.

To all whom, it muy concern.'

Be it known that I, OTTO DUNKEL, a citizen of the United States, residing at Lincoln, in the county of Lancaster and State of N ebraska, have invented certain ner and useful Improvements in Burglar-Alarms; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to burglar-alarms,l and its object is to provide a simple device of this character adapted to be connected to a door-frame and which will be actuated whenever'the door is opened so as to depress a push-button adapted to complete a circuit containing an electric bell or other suitable alarm.

The invention consists of a casing in which is mounted a spring-pressed plunger which is held normally retracted by a catch lying in the path of the door. This plun er when released is adapted to actuate a nger which bears against and is adapted to push the button of an electric circuit.

The invention also consists in further novel construction and combination of parts hereinafter more fully described and claimed.

In the accompanying drawings I have shown the preferred form of my invention.

In the drawings, Figure 1 is a front elevation of my improved burglar-alarm and showing a portion of a door and door-frame. Fig. 2 is a section on line Qc rc, Fig. 1, showing a diagrammatic view of an alarmbell and the circuit-wires leading from the bell to the ush-button. Fig. 3 is a view similar to dig. 2, but showing the positions assumed by the parts subsequent to the actuation thereof.

Referring to the figures by numerals of reference, 1 is a casing or .housing of any suitable form having ears 2 therein and extending from the base thereof, said ears constituting guides for a plun er 3. A spring 4 surrounds that portion of t e plunger between the ears and contacts at opposite ends with one of the ears and with a pin 5 extending through the plunger, respectively. A notch 6 is produced at one end of the plunger and is adapt ed to be automatically engaged by the hooked end 7 of a bell-crank lever 8, which is pivoted between ears 9, extending from one end of the casing. A spring 10 serves to throw the hook 7 automatically into engage* ment with the notch (i. An arm l1 extends from one end of the plunger and has a heel 12 at its point of connection with the plunger, saidv heel being adapted to ride against a raised portion 14, formed upon a finger 15, which is pivoted to the casing 1 and has a block 16 at its free end adapted to contact with a push-button 17. A hook 18 is pivoted to the casing and normally rests upon the arm 11.

A device such as herein described is adapted to be secured to a door-frame 19 close to a door 20 and with the arm 8 so disposed as to be contacted with and actuated by the catch 21 of the door-lock. In order to facilitate the actuation of arm 8 in this manner, I preferably adjustably mount a block 22 upon the arm, said block having a lip 23, lying in the path of the catch 21. It will therefore be obvious that when the door is opened the catch 21 will contact with the lip 23 and cause the bell-crank lever to swing against its spring 10 and release the plunger Spring 4 will therefore actuate the plunger and cause its heel 12 to strike the raised portion 14 of finger 15, and said linger will de press the push-button 17 and cause the completion of any circuit connected thereto and cause the sounding of an alarm.

A spring 24 is preferably employed for ren turning the finger 15 to its initial position after the plunger has been removed therefrom. Should it be desired to lock the plunger so that it will not be actuated by the opening of the door, it is merely necessary to draw it backward a sufficient distance to allow the hook 18 to drop in front thereof. While the lock is preferably actuated by means of the catch 21 of the door-lock, it can, if desired, be so dis ioscd as to be operated by the edge of the oor coming into contact therewith.

In Fig. 2 of the drawings I have shown a diagrammatic view of a signaling system in which I have employed a gong 24, said gong bein connected to the push-button by the usua form of circuit-wires 25, said circuit having a batter r 26 therein.

Havin thus ully described my invention, what I c aim as new, and desire to secure by Letters Patent, is-

1. In a device of the character described, the combination with a movable finger; of a plunger, means for automatically actuating IOO the plunger to contact with and o erate the finger and a lock for holding the p unger out of engagement with the linger.

2. In a device of the character described, the combination with a casing; of a spring pressed )lunger slidably mounted therein, a pivoted ock engaging and ada ted to hold the plunger and a finger movab y connected to the easing and normally in the path of and adapted to be actuated by the plunger.

3. In a device of the character described the combination with a casing,l of a springpressed plunger therein, a finger pivoted to the casing and normally in the path of' the plunger, a locking-lever engaging the plunger and adapted to hold the samenormally out of engagement with the finger and a lip adjustably mounted upon the lever.

4. In a device of the character described the combination with a` casing; of a s ringpressed plunger slidably mounted within the casing, a pivoted fin er connected to the casing and normally wit 1in the path ofthe plunger, a lockin lever adapted to automatically engage the punger and hold it a ainst movement, and means connected to t 1e casing for preventing the actuation of the plunger and i, lip adjustably mounted upon the lockingever.

5. The combination with a door and a door-frame; of a casing connected to the frame, a s ring-pressed plunger Within the casing, a Vmger movably connected to the casing and normally Within the path of the plunger, a locking-lever pivotally connected to the frame and adapted to automatically engage the plunger and hold it against Inovement and a lip upon the lever and within the path of the door.

6. The combination with a door, a doorframe and a push-button upon the frame; of a casing, a spring-pressed plunger mounted within the casin a Enger movably connected with the casmg and adapted to contact with and actuate the push-button, said iinger normally in the path of the plun fer, a lockin -lever adapted to automatical y engage t e plunger and hold it against Inovement and a lip adjustably mounted upon the lever and in the path of the door.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

OTTO DUNKEL.

Witnesses:

H. N. COLMAN. B. F. NoRvAL. 

